1/* SPDX-License-Identifier: GPL-2.0-or-later */ 2/* 3 * INET An implementation of the TCP/IP protocol suite for the LINUX 4 * operating system. INET is implemented using the BSD Socket 5 * interface as the means of communication with the user level. 6 * 7 * Definitions for the IP module. 8 * 9 * Version: @(#)ip.h 1.0.2 05/07/93 10 * 11 * Authors: Ross Biro 12 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 13 * Alan Cox, <gw4pts@gw4pts.ampr.org> 14 * 15 * Changes: 16 * Mike McLagan : Routing by source 17 */ 18#ifndef _IP_H 19#define _IP_H 20 21#include <linux/types.h> 22#include <linux/ip.h> 23#include <linux/in.h> 24#include <linux/skbuff.h> 25#include <linux/jhash.h> 26#include <linux/sockptr.h> 27 28#include <net/inet_sock.h> 29#include <net/route.h> 30#include <net/snmp.h> 31#include <net/flow.h> 32#include <net/flow_dissector.h> 33#include <net/netns/hash.h> 34#include <net/lwtunnel.h> 35 36#define IPV4_MAX_PMTU 65535U /* RFC 2675, Section 5.1 */ 37#define IPV4_MIN_MTU 68 /* RFC 791 */ 38 39extern unsigned int sysctl_fib_sync_mem; 40extern unsigned int sysctl_fib_sync_mem_min; 41extern unsigned int sysctl_fib_sync_mem_max; 42 43struct sock; 44 45struct inet_skb_parm { 46 int iif; 47 struct ip_options opt; /* Compiled IP options */ 48 u16 flags; 49 50#define IPSKB_FORWARDED BIT(0) 51#define IPSKB_XFRM_TUNNEL_SIZE BIT(1) 52#define IPSKB_XFRM_TRANSFORMED BIT(2) 53#define IPSKB_FRAG_COMPLETE BIT(3) 54#define IPSKB_REROUTED BIT(4) 55#define IPSKB_DOREDIRECT BIT(5) 56#define IPSKB_FRAG_PMTU BIT(6) 57#define IPSKB_L3SLAVE BIT(7) 58#define IPSKB_NOPOLICY BIT(8) 59#define IPSKB_MULTIPATH BIT(9) 60 61 u16 frag_max_size; 62}; 63 64static inline bool ipv4_l3mdev_skb(u16 flags) 65{ 66 return !!(flags & IPSKB_L3SLAVE); 67} 68 69static inline unsigned int ip_hdrlen(const struct sk_buff *skb) 70{ 71 return ip_hdr(skb)->ihl * 4; 72} 73 74struct ipcm_cookie { 75 struct sockcm_cookie sockc; 76 __be32 addr; 77 int oif; 78 struct ip_options_rcu *opt; 79 __u8 protocol; 80 __u8 ttl; 81 __s16 tos; 82 char priority; 83 __u16 gso_size; 84}; 85 86static inline void ipcm_init(struct ipcm_cookie *ipcm) 87{ 88 *ipcm = (struct ipcm_cookie) { .tos = -1 }; 89} 90 91static inline void ipcm_init_sk(struct ipcm_cookie *ipcm, 92 const struct inet_sock *inet) 93{ 94 ipcm_init(ipcm); 95 96 ipcm->sockc.mark = inet->sk.sk_mark; 97 ipcm->sockc.tsflags = inet->sk.sk_tsflags; 98 ipcm->oif = inet->sk.sk_bound_dev_if; 99 ipcm->addr = inet->inet_saddr; 100 ipcm->protocol = inet->inet_num; 101} 102 103#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb)) 104#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb)) 105 106/* return enslaved device index if relevant */ 107static inline int inet_sdif(struct sk_buff *skb) 108{ 109#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV) 110 if (skb && ipv4_l3mdev_skb(IPCB(skb)->flags)) 111 return IPCB(skb)->iif; 112#endif 113 return 0; 114} 115 116/* Special input handler for packets caught by router alert option. 117 They are selected only by protocol field, and then processed likely 118 local ones; but only if someone wants them! Otherwise, router 119 not running rsvpd will kill RSVP. 120 121 It is user level problem, what it will make with them. 122 I have no idea, how it will masquearde or NAT them (it is joke, joke :-)), 123 but receiver should be enough clever f.e. to forward mtrace requests, 124 sent to multicast group to reach destination designated router. 125 */ 126 127struct ip_ra_chain { 128 struct ip_ra_chain __rcu *next; 129 struct sock *sk; 130 union { 131 void (*destructor)(struct sock *); 132 struct sock *saved_sk; 133 }; 134 struct rcu_head rcu; 135}; 136 137/* IP flags. */ 138#define IP_CE 0x8000 /* Flag: "Congestion" */ 139#define IP_DF 0x4000 /* Flag: "Don't Fragment" */ 140#define IP_MF 0x2000 /* Flag: "More Fragments" */ 141#define IP_OFFSET 0x1FFF /* "Fragment Offset" part */ 142 143#define IP_FRAG_TIME (30 * HZ) /* fragment lifetime */ 144 145struct msghdr; 146struct net_device; 147struct packet_type; 148struct rtable; 149struct sockaddr; 150 151int igmp_mc_init(void); 152 153/* 154 * Functions provided by ip.c 155 */ 156 157int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, 158 __be32 saddr, __be32 daddr, 159 struct ip_options_rcu *opt, u8 tos); 160int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, 161 struct net_device *orig_dev); 162void ip_list_rcv(struct list_head *head, struct packet_type *pt, 163 struct net_device *orig_dev); 164int ip_local_deliver(struct sk_buff *skb); 165void ip_protocol_deliver_rcu(struct net *net, struct sk_buff *skb, int proto); 166int ip_mr_input(struct sk_buff *skb); 167int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb); 168int ip_mc_output(struct net *net, struct sock *sk, struct sk_buff *skb); 169int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, 170 int (*output)(struct net *, struct sock *, struct sk_buff *)); 171 172struct ip_fraglist_iter { 173 struct sk_buff *frag; 174 struct iphdr *iph; 175 int offset; 176 unsigned int hlen; 177}; 178 179void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph, 180 unsigned int hlen, struct ip_fraglist_iter *iter); 181void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter); 182 183static inline struct sk_buff *ip_fraglist_next(struct ip_fraglist_iter *iter) 184{ 185 struct sk_buff *skb = iter->frag; 186 187 iter->frag = skb->next; 188 skb_mark_not_on_list(skb); 189 190 return skb; 191} 192 193struct ip_frag_state { 194 bool DF; 195 unsigned int hlen; 196 unsigned int ll_rs; 197 unsigned int mtu; 198 unsigned int left; 199 int offset; 200 int ptr; 201 __be16 not_last_frag; 202}; 203 204void ip_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int ll_rs, 205 unsigned int mtu, bool DF, struct ip_frag_state *state); 206struct sk_buff *ip_frag_next(struct sk_buff *skb, 207 struct ip_frag_state *state); 208 209void ip_send_check(struct iphdr *ip); 210int __ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 211int ip_local_out(struct net *net, struct sock *sk, struct sk_buff *skb); 212 213int __ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 214 __u8 tos); 215void ip_init(void); 216int ip_append_data(struct sock *sk, struct flowi4 *fl4, 217 int getfrag(void *from, char *to, int offset, int len, 218 int odd, struct sk_buff *skb), 219 void *from, int len, int protolen, 220 struct ipcm_cookie *ipc, 221 struct rtable **rt, 222 unsigned int flags); 223int ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, 224 struct sk_buff *skb); 225ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, 226 int offset, size_t size, int flags); 227struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, 228 struct sk_buff_head *queue, 229 struct inet_cork *cork); 230int ip_send_skb(struct net *net, struct sk_buff *skb); 231int ip_push_pending_frames(struct sock *sk, struct flowi4 *fl4); 232void ip_flush_pending_frames(struct sock *sk); 233struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, 234 int getfrag(void *from, char *to, int offset, 235 int len, int odd, struct sk_buff *skb), 236 void *from, int length, int transhdrlen, 237 struct ipcm_cookie *ipc, struct rtable **rtp, 238 struct inet_cork *cork, unsigned int flags); 239 240int ip_queue_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl); 241 242static inline struct sk_buff *ip_finish_skb(struct sock *sk, struct flowi4 *fl4) 243{ 244 return __ip_make_skb(sk, fl4, &sk->sk_write_queue, &inet_sk(sk)->cork.base); 245} 246 247static inline __u8 get_rttos(struct ipcm_cookie* ipc, struct inet_sock *inet) 248{ 249 return (ipc->tos != -1) ? RT_TOS(ipc->tos) : RT_TOS(inet->tos); 250} 251 252static inline __u8 get_rtconn_flags(struct ipcm_cookie* ipc, struct sock* sk) 253{ 254 return (ipc->tos != -1) ? RT_CONN_FLAGS_TOS(sk, ipc->tos) : RT_CONN_FLAGS(sk); 255} 256 257/* datagram.c */ 258int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 259int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); 260 261void ip4_datagram_release_cb(struct sock *sk); 262 263struct ip_reply_arg { 264 struct kvec iov[1]; 265 int flags; 266 __wsum csum; 267 int csumoffset; /* u16 offset of csum in iov[0].iov_base */ 268 /* -1 if not needed */ 269 int bound_dev_if; 270 u8 tos; 271 kuid_t uid; 272}; 273 274#define IP_REPLY_ARG_NOSRCCHECK 1 275 276static inline __u8 ip_reply_arg_flowi_flags(const struct ip_reply_arg *arg) 277{ 278 return (arg->flags & IP_REPLY_ARG_NOSRCCHECK) ? FLOWI_FLAG_ANYSRC : 0; 279} 280 281void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, 282 const struct ip_options *sopt, 283 __be32 daddr, __be32 saddr, 284 const struct ip_reply_arg *arg, 285 unsigned int len, u64 transmit_time); 286 287#define IP_INC_STATS(net, field) SNMP_INC_STATS64((net)->mib.ip_statistics, field) 288#define __IP_INC_STATS(net, field) __SNMP_INC_STATS64((net)->mib.ip_statistics, field) 289#define IP_ADD_STATS(net, field, val) SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 290#define __IP_ADD_STATS(net, field, val) __SNMP_ADD_STATS64((net)->mib.ip_statistics, field, val) 291#define IP_UPD_PO_STATS(net, field, val) SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 292#define __IP_UPD_PO_STATS(net, field, val) __SNMP_UPD_PO_STATS64((net)->mib.ip_statistics, field, val) 293#define NET_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.net_statistics, field) 294#define __NET_INC_STATS(net, field) __SNMP_INC_STATS((net)->mib.net_statistics, field) 295#define NET_ADD_STATS(net, field, adnd) SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 296#define __NET_ADD_STATS(net, field, adnd) __SNMP_ADD_STATS((net)->mib.net_statistics, field, adnd) 297 298u64 snmp_get_cpu_field(void __percpu *mib, int cpu, int offct); 299unsigned long snmp_fold_field(void __percpu *mib, int offt); 300#if BITS_PER_LONG==32 301u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 302 size_t syncp_offset); 303u64 snmp_fold_field64(void __percpu *mib, int offt, size_t sync_off); 304#else 305static inline u64 snmp_get_cpu_field64(void __percpu *mib, int cpu, int offct, 306 size_t syncp_offset) 307{ 308 return snmp_get_cpu_field(mib, cpu, offct); 309 310} 311 312static inline u64 snmp_fold_field64(void __percpu *mib, int offt, size_t syncp_off) 313{ 314 return snmp_fold_field(mib, offt); 315} 316#endif 317 318#define snmp_get_cpu_field64_batch(buff64, stats_list, mib_statistic, offset) \ 319{ \ 320 int i, c; \ 321 for_each_possible_cpu(c) { \ 322 for (i = 0; stats_list[i].name; i++) \ 323 buff64[i] += snmp_get_cpu_field64( \ 324 mib_statistic, \ 325 c, stats_list[i].entry, \ 326 offset); \ 327 } \ 328} 329 330#define snmp_get_cpu_field_batch(buff, stats_list, mib_statistic) \ 331{ \ 332 int i, c; \ 333 for_each_possible_cpu(c) { \ 334 for (i = 0; stats_list[i].name; i++) \ 335 buff[i] += snmp_get_cpu_field( \ 336 mib_statistic, \ 337 c, stats_list[i].entry); \ 338 } \ 339} 340 341void inet_get_local_port_range(struct net *net, int *low, int *high); 342 343#ifdef CONFIG_SYSCTL 344static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port) 345{ 346 if (!net->ipv4.sysctl_local_reserved_ports) 347 return false; 348 return test_bit(port, net->ipv4.sysctl_local_reserved_ports); 349} 350 351static inline bool sysctl_dev_name_is_allowed(const char *name) 352{ 353 return strcmp(name, "default") != 0 && strcmp(name, "all") != 0; 354} 355 356static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) 357{ 358 return port < READ_ONCE(net->ipv4.sysctl_ip_prot_sock); 359} 360 361#else 362static inline bool inet_is_local_reserved_port(struct net *net, unsigned short port) 363{ 364 return false; 365} 366 367static inline bool inet_port_requires_bind_service(struct net *net, unsigned short port) 368{ 369 return port < PROT_SOCK; 370} 371#endif 372 373__be32 inet_current_timestamp(void); 374 375/* From inetpeer.c */ 376extern int inet_peer_threshold; 377extern int inet_peer_minttl; 378extern int inet_peer_maxttl; 379 380void ipfrag_init(void); 381 382void ip_static_sysctl_init(void); 383 384#define IP4_REPLY_MARK(net, mark) \ 385 (READ_ONCE((net)->ipv4.sysctl_fwmark_reflect) ? (mark) : 0) 386 387static inline bool ip_is_fragment(const struct iphdr *iph) 388{ 389 return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0; 390} 391 392#ifdef CONFIG_INET 393#include <net/dst.h> 394 395/* The function in 2.2 was invalid, producing wrong result for 396 * check=0xFEFF. It was noticed by Arthur Skawina _year_ ago. --ANK(000625) */ 397static inline 398int ip_decrease_ttl(struct iphdr *iph) 399{ 400 u32 check = (__force u32)iph->check; 401 check += (__force u32)htons(0x0100); 402 iph->check = (__force __sum16)(check + (check>=0xFFFF)); 403 return --iph->ttl; 404} 405 406static inline int ip_mtu_locked(const struct dst_entry *dst) 407{ 408 const struct rtable *rt = (const struct rtable *)dst; 409 410 return rt->rt_mtu_locked || dst_metric_locked(dst, RTAX_MTU); 411} 412 413static inline 414int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) 415{ 416 u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); 417 418 return pmtudisc == IP_PMTUDISC_DO || 419 (pmtudisc == IP_PMTUDISC_WANT && 420 !ip_mtu_locked(dst)); 421} 422 423static inline bool ip_sk_accept_pmtu(const struct sock *sk) 424{ 425 return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && 426 inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; 427} 428 429static inline bool ip_sk_use_pmtu(const struct sock *sk) 430{ 431 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; 432} 433 434static inline bool ip_sk_ignore_df(const struct sock *sk) 435{ 436 return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || 437 inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; 438} 439 440static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, 441 bool forwarding) 442{ 443 struct net *net = dev_net(dst->dev); 444 unsigned int mtu; 445 446 if (READ_ONCE(net->ipv4.sysctl_ip_fwd_use_pmtu) || 447 ip_mtu_locked(dst) || 448 !forwarding) 449 return dst_mtu(dst); 450 451 /* 'forwarding = true' case should always honour route mtu */ 452 mtu = dst_metric_raw(dst, RTAX_MTU); 453 if (!mtu) 454 mtu = min(READ_ONCE(dst->dev->mtu), IP_MAX_MTU); 455 456 return mtu - lwtunnel_headroom(dst->lwtstate, mtu); 457} 458 459static inline unsigned int ip_skb_dst_mtu(struct sock *sk, 460 const struct sk_buff *skb) 461{ 462 unsigned int mtu; 463 464 if (!sk || !sk_fullsock(sk) || ip_sk_use_pmtu(sk)) { 465 bool forwarding = IPCB(skb)->flags & IPSKB_FORWARDED; 466 467 return ip_dst_mtu_maybe_forward(skb_dst(skb), forwarding); 468 } 469 470 mtu = min(READ_ONCE(skb_dst(skb)->dev->mtu), IP_MAX_MTU); 471 return mtu - lwtunnel_headroom(skb_dst(skb)->lwtstate, mtu); 472} 473 474struct dst_metrics *ip_fib_metrics_init(struct net *net, struct nlattr *fc_mx, 475 int fc_mx_len, 476 struct netlink_ext_ack *extack); 477static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics) 478{ 479 if (fib_metrics != &dst_default_metrics && 480 refcount_dec_and_test(&fib_metrics->refcnt)) 481 kfree(fib_metrics); 482} 483 484/* ipv4 and ipv6 both use refcounted metrics if it is not the default */ 485static inline 486void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics) 487{ 488 dst_init_metrics(dst, fib_metrics->metrics, true); 489 490 if (fib_metrics != &dst_default_metrics) { 491 dst->_metrics |= DST_METRICS_REFCOUNTED; 492 refcount_inc(&fib_metrics->refcnt); 493 } 494} 495 496static inline 497void ip_dst_metrics_put(struct dst_entry *dst) 498{ 499 struct dst_metrics *p = (struct dst_metrics *)DST_METRICS_PTR(dst); 500 501 if (p != &dst_default_metrics && refcount_dec_and_test(&p->refcnt)) 502 kfree(p); 503} 504 505u32 ip_idents_reserve(u32 hash, int segs); 506void __ip_select_ident(struct net *net, struct iphdr *iph, int segs); 507 508static inline void ip_select_ident_segs(struct net *net, struct sk_buff *skb, 509 struct sock *sk, int segs) 510{ 511 struct iphdr *iph = ip_hdr(skb); 512 513 /* We had many attacks based on IPID, use the private 514 * generator as much as we can. 515 */ 516 if (sk && inet_sk(sk)->inet_daddr) { 517 iph->id = htons(inet_sk(sk)->inet_id); 518 inet_sk(sk)->inet_id += segs; 519 return; 520 } 521 if ((iph->frag_off & htons(IP_DF)) && !skb->ignore_df) { 522 iph->id = 0; 523 } else { 524 /* Unfortunately we need the big hammer to get a suitable IPID */ 525 __ip_select_ident(net, iph, segs); 526 } 527} 528 529static inline void ip_select_ident(struct net *net, struct sk_buff *skb, 530 struct sock *sk) 531{ 532 ip_select_ident_segs(net, skb, sk, 1); 533} 534 535static inline __wsum inet_compute_pseudo(struct sk_buff *skb, int proto) 536{ 537 return csum_tcpudp_nofold(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr, 538 skb->len, proto, 0); 539} 540 541/* copy IPv4 saddr & daddr to flow_keys, possibly using 64bit load/store 542 * Equivalent to : flow->v4addrs.src = iph->saddr; 543 * flow->v4addrs.dst = iph->daddr; 544 */ 545static inline void iph_to_flow_copy_v4addrs(struct flow_keys *flow, 546 const struct iphdr *iph) 547{ 548 BUILD_BUG_ON(offsetof(typeof(flow->addrs), v4addrs.dst) != 549 offsetof(typeof(flow->addrs), v4addrs.src) + 550 sizeof(flow->addrs.v4addrs.src)); 551 memcpy(&flow->addrs.v4addrs, &iph->addrs, sizeof(flow->addrs.v4addrs)); 552 flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS; 553} 554 555static inline __wsum inet_gro_compute_pseudo(struct sk_buff *skb, int proto) 556{ 557 const struct iphdr *iph = skb_gro_network_header(skb); 558 559 return csum_tcpudp_nofold(iph->saddr, iph->daddr, 560 skb_gro_len(skb), proto, 0); 561} 562 563/* 564 * Map a multicast IP onto multicast MAC for type ethernet. 565 */ 566 567static inline void ip_eth_mc_map(__be32 naddr, char *buf) 568{ 569 __u32 addr=ntohl(naddr); 570 buf[0]=0x01; 571 buf[1]=0x00; 572 buf[2]=0x5e; 573 buf[5]=addr&0xFF; 574 addr>>=8; 575 buf[4]=addr&0xFF; 576 addr>>=8; 577 buf[3]=addr&0x7F; 578} 579 580/* 581 * Map a multicast IP onto multicast MAC for type IP-over-InfiniBand. 582 * Leave P_Key as 0 to be filled in by driver. 583 */ 584 585static inline void ip_ib_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 586{ 587 __u32 addr; 588 unsigned char scope = broadcast[5] & 0xF; 589 590 buf[0] = 0; /* Reserved */ 591 buf[1] = 0xff; /* Multicast QPN */ 592 buf[2] = 0xff; 593 buf[3] = 0xff; 594 addr = ntohl(naddr); 595 buf[4] = 0xff; 596 buf[5] = 0x10 | scope; /* scope from broadcast address */ 597 buf[6] = 0x40; /* IPv4 signature */ 598 buf[7] = 0x1b; 599 buf[8] = broadcast[8]; /* P_Key */ 600 buf[9] = broadcast[9]; 601 buf[10] = 0; 602 buf[11] = 0; 603 buf[12] = 0; 604 buf[13] = 0; 605 buf[14] = 0; 606 buf[15] = 0; 607 buf[19] = addr & 0xff; 608 addr >>= 8; 609 buf[18] = addr & 0xff; 610 addr >>= 8; 611 buf[17] = addr & 0xff; 612 addr >>= 8; 613 buf[16] = addr & 0x0f; 614} 615 616static inline void ip_ipgre_mc_map(__be32 naddr, const unsigned char *broadcast, char *buf) 617{ 618 if ((broadcast[0] | broadcast[1] | broadcast[2] | broadcast[3]) != 0) 619 memcpy(buf, broadcast, 4); 620 else 621 memcpy(buf, &naddr, sizeof(naddr)); 622} 623 624#if IS_ENABLED(CONFIG_IPV6) 625#include <linux/ipv6.h> 626#endif 627 628static __inline__ void inet_reset_saddr(struct sock *sk) 629{ 630 inet_sk(sk)->inet_rcv_saddr = inet_sk(sk)->inet_saddr = 0; 631#if IS_ENABLED(CONFIG_IPV6) 632 if (sk->sk_family == PF_INET6) { 633 struct ipv6_pinfo *np = inet6_sk(sk); 634 635 memset(&np->saddr, 0, sizeof(np->saddr)); 636 memset(&sk->sk_v6_rcv_saddr, 0, sizeof(sk->sk_v6_rcv_saddr)); 637 } 638#endif 639} 640 641#endif 642 643static inline unsigned int ipv4_addr_hash(__be32 ip) 644{ 645 return (__force unsigned int) ip; 646} 647 648static inline u32 ipv4_portaddr_hash(const struct net *net, 649 __be32 saddr, 650 unsigned int port) 651{ 652 return jhash_1word((__force u32)saddr, net_hash_mix(net)) ^ port; 653} 654 655bool ip_call_ra_chain(struct sk_buff *skb); 656 657/* 658 * Functions provided by ip_fragment.c 659 */ 660 661enum ip_defrag_users { 662 IP_DEFRAG_LOCAL_DELIVER, 663 IP_DEFRAG_CALL_RA_CHAIN, 664 IP_DEFRAG_CONNTRACK_IN, 665 __IP_DEFRAG_CONNTRACK_IN_END = IP_DEFRAG_CONNTRACK_IN + USHRT_MAX, 666 IP_DEFRAG_CONNTRACK_OUT, 667 __IP_DEFRAG_CONNTRACK_OUT_END = IP_DEFRAG_CONNTRACK_OUT + USHRT_MAX, 668 IP_DEFRAG_CONNTRACK_BRIDGE_IN, 669 __IP_DEFRAG_CONNTRACK_BRIDGE_IN = IP_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX, 670 IP_DEFRAG_VS_IN, 671 IP_DEFRAG_VS_OUT, 672 IP_DEFRAG_VS_FWD, 673 IP_DEFRAG_AF_PACKET, 674 IP_DEFRAG_MACVLAN, 675}; 676 677/* Return true if the value of 'user' is between 'lower_bond' 678 * and 'upper_bond' inclusively. 679 */ 680static inline bool ip_defrag_user_in_between(u32 user, 681 enum ip_defrag_users lower_bond, 682 enum ip_defrag_users upper_bond) 683{ 684 return user >= lower_bond && user <= upper_bond; 685} 686 687int ip_defrag(struct net *net, struct sk_buff *skb, u32 user); 688#ifdef CONFIG_INET 689struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user); 690#else 691static inline struct sk_buff *ip_check_defrag(struct net *net, struct sk_buff *skb, u32 user) 692{ 693 return skb; 694} 695#endif 696 697/* 698 * Functions provided by ip_forward.c 699 */ 700 701int ip_forward(struct sk_buff *skb); 702 703/* 704 * Functions provided by ip_options.c 705 */ 706 707void ip_options_build(struct sk_buff *skb, struct ip_options *opt, 708 __be32 daddr, struct rtable *rt, int is_frag); 709 710int __ip_options_echo(struct net *net, struct ip_options *dopt, 711 struct sk_buff *skb, const struct ip_options *sopt); 712static inline int ip_options_echo(struct net *net, struct ip_options *dopt, 713 struct sk_buff *skb) 714{ 715 return __ip_options_echo(net, dopt, skb, &IPCB(skb)->opt); 716} 717 718void ip_options_fragment(struct sk_buff *skb); 719int __ip_options_compile(struct net *net, struct ip_options *opt, 720 struct sk_buff *skb, __be32 *info); 721int ip_options_compile(struct net *net, struct ip_options *opt, 722 struct sk_buff *skb); 723int ip_options_get(struct net *net, struct ip_options_rcu **optp, 724 sockptr_t data, int optlen); 725void ip_options_undo(struct ip_options *opt); 726void ip_forward_options(struct sk_buff *skb); 727int ip_options_rcv_srr(struct sk_buff *skb, struct net_device *dev); 728 729/* 730 * Functions provided by ip_sockglue.c 731 */ 732 733void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb); 734void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk, 735 struct sk_buff *skb, int tlen, int offset); 736int ip_cmsg_send(struct sock *sk, struct msghdr *msg, 737 struct ipcm_cookie *ipc, bool allow_ipv6); 738int ip_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, 739 unsigned int optlen); 740int ip_getsockopt(struct sock *sk, int level, int optname, char __user *optval, 741 int __user *optlen); 742int ip_ra_control(struct sock *sk, unsigned char on, 743 void (*destructor)(struct sock *)); 744 745int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len); 746void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port, 747 u32 info, u8 *payload); 748void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 dport, 749 u32 info); 750 751static inline void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb) 752{ 753 ip_cmsg_recv_offset(msg, skb->sk, skb, 0, 0); 754} 755 756bool icmp_global_allow(void); 757extern int sysctl_icmp_msgs_per_sec; 758extern int sysctl_icmp_msgs_burst; 759 760#ifdef CONFIG_PROC_FS 761int ip_misc_proc_init(void); 762#endif 763 764int rtm_getroute_parse_ip_proto(struct nlattr *attr, u8 *ip_proto, u8 family, 765 struct netlink_ext_ack *extack); 766 767static inline bool inetdev_valid_mtu(unsigned int mtu) 768{ 769 return likely(mtu >= IPV4_MIN_MTU); 770} 771 772void ip_sock_set_freebind(struct sock *sk); 773int ip_sock_set_mtu_discover(struct sock *sk, int val); 774void ip_sock_set_pktinfo(struct sock *sk); 775void ip_sock_set_recverr(struct sock *sk); 776void ip_sock_set_tos(struct sock *sk, int val); 777 778#endif /* _IP_H */ 779